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Great design. Personally I like industrial and functional looking vents over decorative. You may want to do a test with vent sizes. I had a system with 1/4 vent openings and 1/4 material (1/4 = approx 6mm) thickness that caused swooshing sounds due to to the tunnel effect of the vents. Something to keep in mind. The swooshing sounds ended up causing more noise than the fan.
